Fluid compressor



March 20, 1951 w. w. PAGET FLUID COMPRESSOR Filed Oct. 15, 1944 2Sheets-Sheet 1 1220622202 Mia zipajei. 3 ,zm-l mw March 20, 1951 w. w.PAGET FLUID COMPRESSOR 2 Sheets-Sheet 2 Filed Oct. 15, 1944 4 7f 60 174111 H 6/ .53 Jo 64y h 5 i 4.? MM a 77 v v 4y Patented Mar. 20, 1951FLUID COMPRESSOR Win W. Paget, chigan City, Ind-, assi nor to JoyManufacturing Company, acorporati'on of Pennsylvania Application Octobers, 1944, :Serial no. 558,554

15 Claims. 1

'My invention relates to fluid compressors .or pumps, :and vmoreparticularly to compressors for air or other gaseous rfluid.

It is desirable that the temperature of a fluid discharged from acompressor be maintained low, and this may ,be assisted by a reductionin the heating of the .fluid flowing to the compressor through theintake passages. Since the .in. take and discharge passages :of acompressor are usually in close proximity to each other, there should beprovided some .means for reducing the transfer of heat .from.thecompressed fluid to the fluid in the intake. It is .also desirablethat the compressor be provided with .an unloading .device whichoperatesata predetermineddischarge pressure to cutoff the :supply .of fluid to,a receiver or to some point of use, and this unload- .ing device should=operategso as to prevent as much as possible the heating of .thecompresor during continued operation of the latter after .unloadingtakes place. It .is also desirable to .start the compressor under noload.

In .a preferred form of .my invention there .is shown .a compressorhaving .intake passages which are lined with an insulating material toreduce the transfer of heat to the fluid therein. Insulation is alsoprovided to reduce the transter of heat to the intake connectionsleading to the compressor cylinders. The discharge passages areformedina material which is .a good heat conductor, and these passagesare .so arranged that large cooling surfacesare obtained. "-I heunloading device .is designed to vcut off the -flow of fluid Lto.-.theintake and to ventthe discharge passages which may be associated with.ac0oling device such as an aftereooler so that .any rluid leaking tothe intake passages will not be :compressed and discharged against ahigh ."pressure in the discharge line. The-venting of :the dischargeline also assures against the ,de-

(C1. 23.0-r24) V Eliveryof any fluid toa receiver or to :a point .of

pylinder intake to be attended by ,relief of the 5 load onthe-discharge-sideof-thecylinder. In a preferred embodiment :an intakeclosure valve, a -,discharge -line vent. valve and a :common elementmovable upon I predetermined discharge pressure variations automaticallyto fiefiiect -.i-ntake closure valve closing and discharge line ventvalve .opening, may ,be provided. Qesirably the two valve means may/insuch preferred embodiment, be coaxiall y arranged and the commonoperating element ,may be a fluid operated piston asso- .ciated with oneof said valvemeans, and preferably the intake closure valve means.

vtin object .of my invention is to provide an improved pump-orcompressor. Another object of my invention is to provide a compressorhaving improved means for preventing the heating of the fluid therein..Still another object is to provide a compressor having improved meansfor preventing the transfer of heat etween the in.- take and d chargepas ages. Yet another ob- .J'ect is to sprovidela compressor havingimproved lo in mean ,An ther object is t prov for a compressor animproved unloading means which .is operative to control the flow offluid relative .to the intake and discharge passages. .still anotherobject is to provide an improved unloading means which isoperative at apredetermined compressor .discharge pressure for cutt n th flow o fluidt the comp esso o intake and venting the ..compressor discharge. Anotherobject ;is to provide an improved ,unlo ng m ans havin valve means forcontrol- ;ling-therflowof ,fluid relative to the intake end of acompressor and having other valve means for controlling the venting ofthe compressor discharge, and .means responsive to compressor,--discharge pressure for actuating each of said valve means. .A still furtherobjectis to provide improved means associated with .an intakeclosure unloader yfor venting the aftercooler of a compressor. Qt-herobjects will appear in the :course of the followingdescription.

I-n the accompanyin drawings there is shown :for purp se o ll stratonpne f rm wh h my invention may assu incur-act ve .In :these drawings:

fig. :1 is .a side .elevational "view of a compressor having :myimprovedunloading .means and insulating means eembodied therein.

Fig. 2 is an enlarged cross-sectional-view, .with certain parts shown:in elevation and other parts omitted to facilitate"illustration, takensubstan- :tialiy on the jline;2.;2 of Fig. -1.

;F ig. ,3115 anerilargedsectionalview taken on .theplanespf ,the line;3fi o f j F. ig. l, and showing theintakeand. discharge manifolds andthe unloading -means associated therewith.

Fig. A is ,a cross-sectional .view taken on the plane of theglinea fidqf.Eis. BL ithpaIt infal Fig. 5 is a view taken on the plane of the line5-5 of Fig. 2 with parts omitted.

Fig. 6 is an enlarged sectional view of the automatic vent valve.

In the illustrative embodiment of my invention there is shown a pumpmechanism or compressor, generally designated l, driven by a power unit2 and delivering fluid to a receiver 3.

The compressor, as shown herein, is of the V-type and includes acrankcase 5 supported by a frame 6 and having two guide cylinders 8 and9 connected thereto, as by bolts ID, in angularly spaced relation.Connected to flanges II at the outer ends of the guide cylinders, as bybolts I2, are compressor cylinders l4'and I5, and attached, as by bolts16, to the outer ends of the compressor cylinders are cylinder heads l1..and IS. The guide cylinders, the compressor cylinders, and the cylinderheads are identical in each pair, so the detailed structure of only oneof each need be shown and described.

Each of the guide cylinders has a guideway 29 for reciprocably guiding acrosshead 2| which is connected by a connecting rod 22 to a crankshaft23 driven by the power unit 2. The crosshead is also connected to apiston rod 25 which is attached to a piston 26 reciprocably mounted in abore 21 in the compressor cylinder. Clamped between the guide cylinderand the compressor cylinder is a plate 29 having an opening 39 throughwhich the piston rod extends, and arranged within the opening 30 is apacking ring 3| sealingly engaging the piston rod. At the lower end ofthe compressor cylinder is a port 32 connecting the space in thecylinder beneath the piston in free communication with the atmosphere.Each of the cylinder heads is provided with an intake passage 33 and adischarge passage 34, the intake and discharge passages communicatingrespectively with the cylinder bore under the control of inlet anddischarge valves 35 and 36. The intake passage 33 is provided with aliner 3! made of an insulating material such as Synthane and operatingto reduce the transfer of heat from the compressed fluid through thecylinder head walls to the fluid in the intake passage. A cap 38 isconnected, as by bolts 39, at the top of each cylinder head and providesan intake chamber 40 into which one of the intake passages 33 opens.Arranged between the cap 38 and the adjacent head portion is a plate 4|made of an insulating material such as that mentioned above so as toreduce the transfer of heat from the adjacent head portion to the cap.Attached to the ca 38, as by bolts 42, is an intake manifold 43 having apassage 44 which communicates freely with each of the chambers 40.Attached to the sides of the cylinder heads, as by bolts '45, is acombined discharge manifold and aftercooler 46 having a passage 4?communicating freely with each of the discharge passages 34. Formed onthe guide cylinders, the compressor cylinders, the cylinder heads, andthe discharge manifold are cooling fins 49, 50, 5| and 52, respectively.I

The intake and discharge manifolds have at their mid-portionsenlargements 53 and 54 which cooperate to provide a housing forunloading means generally designated 55. Formed in the enlargement 53 isa chamber 56 into which a fluid supply conduit 5'! opens, and thischamber communicates past a valve-seat-providing member 58 with thepassage 44 in the intake manifold. A cover plate 59 attached, as bybolts 60, to the top of the enlargement 53 closes the chama manifoldthrough a port 83.

ber 55 and provides a. depending annular portion BI on which a hollowintake closure valve 62 is reciprocably guided. The valve member 62 hasan enlarged portion 63 carrying a packing ring 54 which sliclablyengages the outer walls of the depending portion 6 I, and also has areduced portion 65 extending through the member 58 and through anopening 56 in the opposite wall of the intake manifold. A packing ring68 carried by the intake manifold engages the reduced portion 65 andprevents the escape of fluid from the passage 44 through the opening 65.Between the portions 63 and 65 of the valve member is a portion 10engageable with the member 58 for cutting off the flow of fluid betweenthe chamber 55 and the passage 44. Surrounding the reduced portion 65 isa spring H acting between a wall of the intake manifold and a shoulder12 on the valve member for urging the latter toward its unseatedposition. The interior of the valve member cooperates with the annularportion 5! to form a chamber 14 into which a conduit 15 opens throughthe cover plate 59. Any suitable pilot valve mechanism, not shown, maybe used to connect the conduit 15 alternatively with the receiver orwith atmosphere, depending upon whether receiver pressure is at itsdesired upper limit or so lowered as to make renewed pumping desirable.When the receiver pressure reaches a predetermined maximum value, thevalve member 62 is forced downwardly against the action of the spring Huntil it engages the member 58 and cuts off the flow of fluid from thechamber 56 to the passage 44.

The enlargements 55 and 54 have therebetween a space 18 into which thereduced portion 55 of the valve member 52 projects when the latter ismoved to its lower position. Arranged between the enlargement 54 and thelower side of the intake manifold are shims 19 which are adjusted tolimit the distance at which the portion 65 may extend into the space 18.Between the shims l9 and the intake manifold is a layer of insulatingmaterial 89 to reduce the transfer of heat from the discharge manifoldto the intake manifold. The sides of the space 18 communicate, as shownin Fig. 4, freely with the atmosphere. At the bottom of the space 18 isan enlarged wall portion 8| in the discharge manifold, and this wallportion is provided with a recess 82 opening into the passage 4'! in thedischarge Threaded into the recess 82 is a valve seat member 84 having aport 85 connecting the recess 82 and space 18 in communication with eachother. Received within the recess 82 is a valve member 86 engageablewith the valve seat member 54 for cutting off the flow of fluid throughthe port 85, and a spring 88 acts between the bottom of the recess 82and the valve member 86 for urging the latter into engagement with themember 94. The valve member 88 has a reduced portion 89 extendingthrough the port 85 with sufficient clearance to permit fluid to flowfreely through the latter when the member 36 is moved out of engagementwith the member 84, and the portion 89 extends to a point where it isengageable by the portion 65 of the valve member 52 and is forced to itsopen position when the latter is moved to its closed position. Thelarger portion of the valve body has radial ports through which fluidmay flow from the port 83 and through the hollow interior of the valvebody to the clearance space about the portion 89 (Fig. 6). Theenlargement 54 provides at the lower side of the discharge manifold achamber 9! communicating with a discharge conduit 92 leading to thereceiver 3, and the pasage 41 in the discharge manifold communicatesthrough a port 93 withthe chamber 9| under the control of a valve 94.The valve 94 has a valve stem 95 which is slidably received within abushing 96 carried by a plate 9! closing the chamber 9|, and a spring 98acts between the plate 91 and the valve stem 95 for urging the valve 94toward a position cutting off the flow of fluid through the port 93.

During operation of the compressor when the receiver pressure is low,the valve member 62 is held in its open position by the spring H, andthe valve member 86 is held in its closed position by the spring 88.Fluid then flows from the conduit 51 through the chamber 55 and pastthe,

valve seat member 58 to the intake passage 44 where it is delivered tothe chambers 40 at the outer ends of the cylinder heads I! and [8. Thefluid passes from the chambers iii to the intake passages 33 and isconducted past the inlet valves 35 to the cylinder bores 2'? where it iscompressed and then discharged past the discharge valves 38 to thepassages 34 in the cylinder heads. The compressed fluid flows from thepassages 34 to the discharge pasage 41 in the combined. dischargemanifold and aftercooler.

The valve 34 is opened by the pressure of the fluid in the passage 4'!and fluid then flows past the valve 94 to the chamber 9: where it entersthe discharge conduit 92 and is conducted to the receiver 3. When thereceiver pressure reaches a value suflicient to cause fluid to besupplied to move the valve member 62 against the action of the spring1!, the fluid caused to be delivered from the receiver through theconduit '55 to the interior of the valve member 62 results in the lattermoving to its closed position cutting off the supply of fluid to thepassage 44 in the intake manifold. As the valve member 62 closes, it engages the stem 89 on the valve member 86 and forces the latter to itsopen position for venting fluid from the passage 4'! in the combineddischarge manifold and aftercooler. The valve member 94 then closesagainst the action of the reduced fluid pressure and prevents the escapeof fluid from the receiver. When the pressure in the receiver dropsbelow a predetermined value the conduit is caused to be vented, therebyventing the fluid acting on the valve member 62 resulting in the lattermoving to its open position again. to admit fluid to the intake passage.When the stem of the valve member 62 moves away from the vent valve 86,the latter is moved by its spring to its closed position, cutting offthe vent for the discharge passage. As the pressure builds up in thedischarge manifold, the valve 94 is automatically opened to permit flowof compressed fluid to the receiver. As mentioned above a pilot valvemechanism of conventional form is employed to connect the conduit 15alternatively with the receiver or with the atmosphere, depending uponwhether receiver pressure is at its desired upper limit or has fallen apredetermined amount below such upper limit.

It will be understood that the compressor mechanism shown isv merelyillustrative of an arrangement with which my improved unloading means isadapted for use, and that this unloading means may be used as well witha compressor having one or more than two cylinders.

As a result of my invention there is provided an improved unloadingmeans which is adapted pressor by controlling simultaneously the flow offluid in the intake and discharge passages. By venting the dischargepassages to atmosphere during unloading there is prevented any supply tothe receiver of fluid which may leak past the intake closure valve tothe compressor cylinder where it would be compressed and discharged tothe discharge manifold. By venting the discharge manifold, starting ofthe compressor while loaded is prevented. There is also prevented adischarge of such fluid against any substantial pressure in thedischarge line and resulting in a heating of the compressor during itsunloaded operation. By reason of the insulating of the intake passages,

the fluid delivered to the cylinders is cooler and the discharged fluidis correspondingly cooler.

While there is in this application specifically described one formwhichthe invention may assume in practice, it will be understood thatthis form of the same is shown for purposes of illustration, and thatthe invention may be modified and embodied in various other formswithout departing from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

1. In combination, a compressor having at least one inlet valve and anintake connection and at least one discharge valve and a dischargeconnection, an intake closure type unloader valve for shutting ofi flowthrough said intake connection, a check valve disposed to permit flowfrom said compressor through said discharge connection and to preventflow past said check valve towards said compressor through saiddischarge connection, a vent valve for venting the space between saidcompressor and said check valve by connecting said discharge connectionto atmosphere, and means for effecting closing of said intake closuretype unloader valve and opening of said vent valve to effect unloadingof said compressor and to prevent, during unloaded operation, thedevelopment of excessive temperatures in the compressor due to theraising of the pressure of any fluid which may leak past said intakeclosure type unloader valve through an excessive number of compressions,said means for effecting closing of said intake closure type unloadervalve and opening of said vent valve including means for transmittingmovement from said unloader valve, as it moves towards closed position,to said vent valve, to efiect opening of the latter.

2. In combination, a compressor having at least one inlet valve and anintake connection and at least one discharge valve and a dischargeconnection, an intake closure type unloader valve for shutting ofl flowthrough said intake connection, a check valve disposed to permit flowfrom said compressor through said discharge connection and to preventflow past said check valve towards said compressor through saiddischarge connection, a vent valve for venting the space between saidcompressor and said check valve by connecting said discharge connectionto atmosphere, and means for effecting closing of said intake closuretype unloader valve and opening of said vent valve to effect unloadingof said compressor and to prevent, during unloaded operation, thedevelopment of excessive temperatures in the compressor due to theraising of the pressure of any fluid which may leak past said It intakeclosure type unloader valve through an excessive number of compressions,said means for effecting closing of said intake closure type unloadervalve and opening of said vent valve including abutments in fixedrelation respectively to said intake closure type unloader valve and tosaid vent valve and engaging each other to preclude simultaneousoccupation by said intake closure type unloader valve and said ventvalve of their respective closed positions.

3. In combination, a compressor having at least one inlet valve and anintake connection and at least one discharge valve and a dischargeconnection, an intake closure type unloader valve for shutting off flowthrough said intake connection, a check valve disposed to permit flowfrom said compressor through said discharge connection and to preventflow past said check valve towards said compressor through saiddischarge connection, a vent valve coaxial with said intake closure typeunloader valve for venting the space between said compressor and saidcheck valve by connecting said discharge connection to atmosphere, andmeans for effecting closing of said intake closure type unloader valveand, through movement imparted to it by said intake closure typeunloader valve, opening of said vent valve to effect unloading of saidcompressor and to prevent, during unloaded operation, the development ofexcessive temperatures in the compressor due to the raising of thepressure of any fluid which may leak past said intake closure typeunloader valve through an excessive number of compressions.

4. In combination, in a fluid compressor, cylinder structures arrangedin v-relation, a fluid intake manifold extending between, said cylinderstructures for supplying fluid to them and having an intake connectionspaced from each of its own ends, a fluid discharge manifold extendingbetween said cylinder structures for receiving fluid from them andhaving a discharge connection spaced from each of its own ends, anintake closure type unloader valve associated with said intakeconnection, and a vent valve associated with said discharge connection,said'valves so constructed and arranged that motion is transmited tosaid vent valve to open the-same when said intake closure valve is movedto closed position.

5. The combination set forth in claim 4 in which said valves each have astem and said stems are so relatively constructed and arranged that thestem of said unloader valve contacts the stem of said vent valve andactuates it to open said vent valve as said unloader valve is closed.

6. The combination set forth in claim 4 in which said unloader valve andsaidvent valve are coaxially disposed and oppositely seating and stemmeans is associated with each of said valves in such mutual relationthat the vent valve is unseated by seating movement of said unloadervalve.

'7. In combination, a compressor having an inpositioned that said secondelement when so moved effects actuation of said first element, withresultant substantially concurrent intake closure and terminalconnection venting.

8. In combination, a compressor having an intake and a terminalconnection for the discharge of compressed fluid, and unloading meansfor said compressor including a valve member movable to cut off theadmission of fluid to said intake, a valve member movable to a positionfor venting said terminal connection, an element for moving said lastmentioned valve member to effect venting of said terminal connection,means for moving said first mentioned valve member to closed position,and an element moved with said first mentioned valve member as thelatter is closed and contacting said first mentioned element to move thelatter whereby said second mentioned valve member is moved to openposition on closure of said first mentioned valve member.

9. In a mechanism of the character described, in combination, acompressor, intake and discharge passages for said compressor, andunloading means for said compressor including a valve member movable toa position for cutting ofi the supply of fluid to said intake passage, avalve member movable to a position for venting said discharge passage,one of said valve members engageable by the other of said valve membersand movable by the latter to its position aforesaid, and meansresponsive to compressor discharge pressures for effecting movement ofsaid other of said valve members to its position aforesaid.

10. In a mechanism of the character described, in combination, acompressor having a plurality of compressor cylinders, intake anddischarge manifolds common to said compressor cylinders, and means forunloading said compressor including a valve member movable to a positionfor cutting off the flow of fluid to said intake manifold, a valvemember movable to a position for venting said discharge manifold, saidlast mentioned valve member engageable by said first mentioned valvemember and movable by the latter to its venting position, and meansresponsive to compressor discharge pressure and actuated thereby foreffecting movement of said first mentioned valve member.

11. In a mechanism of the character described, in combination, acompressor having a plurality of compressor cylinders, means for drivingsaid compressor, intake and discharge manifolds common to saidcompressor cylinders, and means for unloading said compressor includinga valve member movable to a position for cutting off the flow of fluidto said intake manifold, a valve member movable to a position forventing said discharge manifold, said first mentioned valve memberresponsive to compressor discharge pres- (sures and movable at apredetermined maximum take and a terminal connection for the discharge 7of compressed fluid, and unloading means for said compressor including avalve member movable to cut off admission of fluid to said intake, avalve member movable to a position for venting said terminal connection,an element for moving one of said valve members as aforesaid, an elementmoved with the other of said valve members as it is moved as aforesaid,and means for moving as aforesaid said valve member having said secondmentioned element movabletherewith. said elements so mutually arrangedand pressure to its closed position, and said second mentioned valvemember engageable by said first mentioned valve member on movement ofthe latter to its closed position and movable thereby to its ventingposition.

I 12. In a compressor, intake and discharge passage means for thecompressor, a receiver with which said discharge passage meanscommunicates, an intake closure unloading device for the compressoroperative to cut off the supply of fluid to said intake passage meanswhen a predetermined compressor discharge pressure is attained, valvemeans past which the fluid in said discharge passage means flows to saidreceiver, and valve means for venting said discharge passage means whenthe compressor is unloaded, said first mentioned valve meansautomatically closing to cut oil communication of said receiver withsaid discharge passage means when the latter is vented.

13. In an apparatus for interrupting the pumping by a compressor and forrelieving the load on the compressor upon starting thereof, incombination, a valve'device positionable to effect supply to orinterrupt the supply to a pump cylinder, a valve device positionable torelieve the load on the discharge side of the pump or to permit thebuilding up of the load, means for moving said first mentioned valve tointerrupt the supply of fluid to be pumped to the cylinder, and means foefiecting the movement of said second mentioned valve automatically toeffect the removal of the load from the pump cylinder when said firstmentioned valve assumes its last mentioned position.

14. In a fluid compressor, a pair of spaced compressor cylinders ofequal size and capacity and each containing a piston, intake anddischarge passage means common to said cylinders and extendingtherebetween, an intake closure unloading device associated with saidintake passage means midway between said cylinders for cutting off fluidsupply concurrently to both cylinders when a predetermined compressordischarge pressure is attained, and a venting device as-' sociated withsaid discharge passage means likewise midway between said cylinders forautomatically concurrently venting the discharges from both cylinderswhen said intake fluid supply is cut oil.

15. In a fluid compressor, a pair of spaced com- 10 pressor cylinders ofequal size and capacity and eachcontaining a piston, intake anddischarge passage means common to said cylinders and extendingtherebetween, a reciever with which said discharge passage meanscommunicates, means associated with said intake passage means midwaybetween said cylinders for cutting off fluid supply concurrently to bothcylinders when a predetermined pressure is attained in said receiver,means associated with said discharge passage means likewise midwaybetween said cylinders for automatically concurrently venting thedischarges from both cylinders when said fluid supply is cut oil, and avalve device for automatically preventing flow of fluid from saidreceiver to the discharges of both cylinders when said discharge passagemeans is vented.

WIN W. PAGET.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,644,077 Blom Oct. 4, 19271,909,972 Le Valley May 23, 1933 2,041,717 Lamberton May 26, 19362,047,489 Pfeifer July 14, 1936 2,137,752 Ferguson Nov. 22, 19382,186,492 Paget Jan. 9, 1940 7 2,221,789 Ferguson Nov. 19, 19402,302,847 Ferguson Nov. 24, 1942 2,312,335 Halleck Mar. 2, 19432,334,209 Lamberton Nov. 16, 1943

